High‐efficiency electromagnetic (EM) functional materials are the core building block of high‐performance EM absorbers and devices, and they are indispensable in various fields ranging from ...industrial manufacture to daily life, or even from national defense security to space exploration. Searching for high‐efficiency EM functional materials and realizing high‐performance EM devices remain great challenges. Herein, a simple solution‐process is developed to rapidly grow gram‐scale organic–inorganic (MAPbX3, X = Cl, Br, I) perovskite microcrystals. They exhibit excellent EM response in multi bands covering microwaves, visible light, and X‐rays. Among them, outstanding microwave absorption performance with multiple absorption bands can be achieved, and their intrinsic EM properties can be tuned by adjusting polar group. An ultra‐wideband bandpass filter with high suppression level of −71.8 dB in the stopband in the GHz band, self‐powered photodetectors with tunable broadband or narrowband photoresponse in the visible‐light band, and a self‐powered X‐ray detector with high sensitivity of 3560 µC Gyair−1 cm−2 in the X‐ray band are designed and realized by precisely regulating the physical features of perovskite and designing a novel planar device structure. These findings open a door toward developing high‐efficiency EM functional materials for realizing high‐performance EM absorbers and devices.
A facile one‐step solution processing method is developed to rapidly prepare gram‐scale MAPbX3 microcrystals. Utilizing its intrinsic electromagnetic (EM) properties, a series of EM devices is designed and fabricated, which can be applied in the fields of ultra‐wideband bandpass filters and multi‐band photodetection covering X‐rays, UV, visible light, and microwaves.
Nitrogen fixation is industrially realized by mass production of ammonia, the principal intermediate nitrogen source for N‐containing organic molecules. Instead, direct C−N bond formation from ...dinitrogen (N2) is of great interest but remains a challenge. Here, by virtue of unique plasma–liquid interactions, we developed an environmentally benign one‐pot approach to directly couple benzene and N2, two naturally abundant yet chemically inert molecules, into value‐added arylamines. Under the optimal conditions, an amination yield of 45 % was rapidly achieved, far better than the reported benzene amination efficiency using ammonia. A tentative reaction mechanism was proposed involving the long‐lived N2 (A3Σu+
) and N2+ species, as evidenced by the key intermediates detected. With a deeper mechanistic understanding and by further optimizing the plasma reactor, the realization of cost‐effective electrical amination of benzene with N2 could become reality.
Molecular N2 was directly fixed into arylamines in a plasma–liquid system at ambient temperature and pressure without transition metal mediation, which provides a green alternative to the hazardous multistep processes as practiced in the traditional method for large‐scale arylamine production.
Although glutathione S-transferases (GST, EC 2.5.1.18) are involved in response to abiotic stress, limited information is available regarding gene function in tomato. In this study, a GST gene from ...tomato, designated LeGSTU2, was cloned and functionally characterized. Expression profile analysis results showed that it was expressed in roots and flowers, and the transcription was induced by salt, osmotic, and heat stress. The gene was then introduced to Arabidopsis by Agrobacterium tumefaciens-mediated transformation. Transgenic Arabidopsis plants were normal in terms of growth and maturity compared with wild-type plants. Transgenic plants also showed an enhanced resistance to salt and osmotic stress induced by NaCl and mannitol. The increased tolerance of transgenic plants was correlated with the changes in proline, malondialdehyde and antioxidative emzymes activities. Our results indicated that the gene from tomato plays a positive role in improving tolerance to salinity and drought stresses in Arabidopsis.
Single molecular nanoparticles (SMNPs) integrating imaging and therapeutic capabilities exhibit unparalleled advantages in cancer theranostics, ranging from excellent biocompatibility, high ...stability, prolonged blood lifetime to abundant tumor accumulation. Herein, we synthesize a sophisticated porphyrin nanocage that is further functionalized with twelve polyethylene glycol arms to prepare SMNPs (porSMNPs). The porphyrin nanocage embedded in porSMNPs can be utilized as a theranostic platform. PET imaging allows dynamic observation of the bio‐distribution of porSMNPs, confirming their excellent circulation time and preferential accumulation at the tumor site, which is attributed to the enhanced permeability and retention effect. Moreover, the cage structure significantly promotes the photosensitizing effect of porSMNs by inhibiting the π–π stacking interactions of the photosensitizers, ablating of the tumors without relapse by taking advantage of photodynamic therapy.
Sophisticated porphyrin nanocages, which can be utilized as a functional platform to develop single molecular nanoparticles, were synthesized. The unique topological structure of the nanocages results in their excellent performance as cancer nanotheranostics, as demonstrated through applications in PET imaging and photodynamic therapy.
This paper considers the event-triggered predictive control(ETPC) problem for linear discrete-time multi-agent systems. To achieve accurate state estimation under event-triggered communication ...between agents, an event-triggered predictive control scheme as well as a novel class of triggering condition are proposed for synchronization of multi-agent systems with single-integrator dynamics, where the control input of each agent no longer remains constant but updates periodically within the time interval between two consecutive triggering instants. Then, the proposed scheme is extended to the general linear multi-agent systems. By comparing with the time-triggered control(TTC) method and the existing event-triggered control(ETC) methods, the control performance of the proposed ETPC scheme is almost the same as that of the TTC approach, and the communication payload between agents is reduced with much less triggering times than existing ETC methods. Finally, two numerical examples are given to verify the theoretical analysis and demonstrate the superiority of the proposed method comparing with some existing methods.
Dissolved organic carbon (DOC) in aquatic environments is an important cycled pool of organic matter on the Earth. Satellite remote sensing provides a useful tool to determine spatiotemporal ...distribution of water quality parameters. Previous DOC remote sensing studies in inland water suffered from either low spatial resolution or low temporal frequency. In this study, we evaluated the potential of jointly using Landsat-8 and Sentinel-2 with high spatial resolution to estimate DOC concentrations in Saginaw River plume regions of Lake Huron. Firstly, CDOM (colored dissolved organic matter) was estimated from images using the known models and then DOC can be derived in terms of the good correlations between DOC and CDOM. The results show that Landsat-8 and Sentinel-2 had acceptable accuracy and good consistency in DOC estimation so that jointly using them can improve the observation frequency. In different seasons from 2013 to 2018, DOC was typically higher in spring and autumn but lower in summer. Monthly spatiotemporal variations of DOC in 2018 were also observed. The image-derived DOC spatiotemporal variations show that DOC was covaried with Saginaw River discharge (r = 0.82) and also weakly and negatively correlated with water temperature (r = −0.6). This study demonstrated that using Landsat-8 and Sentinel-2 together can offer the potential applications for monitoring DOC and water quality dynamic in complex inland water.
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•Landsat-8 and Sentinel-2 DOC models showed acceptable accuracy.•Landsat-8 and Sentinel-2 DOC estimates were consistent within 4.9%.•Monthly spatiotemporal variations of DOC in Lake Huron were observed.•DOC concentrations were significantly influenced by the riverine discharge.
Nanoparticles with unique properties have potential applications in food, medicine, pharmacology, and agriculture industries. Accordingly, many significant researches have been conducted to develop ...novel nanoparticles using chemical and biological techniques. This review focuses on the synthesis of selenium nanoparticles (SeNPs) using polysaccharides as templates. Various instrumental techniques being used to confirm the formation of polysaccharide-SeNPs conjugates and characterize the properties of nanoparticles are also introduced. Finally, the biological activities of the synthesized SeNPs and the influence of structural factors of polysaccharides on the property of synthetic nanocomposites are highlighted. In general, the polysaccharides functionalized SeNPs can be easily obtained using sodium selenite as precursor and ascorbic acid as reductant. The final products having different particle size, morphology, and selenium content exhibit abundant physiological activities. Structural factors of polysacchairdes involving molecular weights, substitution of functional groups, and chain conformation play determinant roles on the properties of nanocomposites, resulting in different biological performances. The review on the achievements and current status of polysaccharides conjugated SeNPs provides insights into this exciting research topic for further studies in the future.
The endoplasmic reticulum (ER) has a central role in the fine-tuning of environmental and internal stimuli. We herein report a ratiometric fluorescent probe, α-Naph, capable of determining basal H2O2 ...in the ER. The probe specifically responds to H2O2. The limit of detection of the probe is as low as 38 nM, making it a feasible sensor to image intracellular basal H2O2. In addition, utilizing its ratiometric property, we are able to measure the concentration of H2O2 in the ER quantitatively, eliminating the error caused by the probe concentration and environment. The intracellular concentration of H2O2 in the ER is calculated to be 0.692 μM under normal conditions and 1.26 μM under the stimulation of phorbol myristate acetate.
Control of self-assembly is significant to the preparation of supramolecular materials and illustration of diversities in either natural or artificial systems. Supra-amphiphiles have remarkable ...advantages in the construction of nanostructures but control of shape and size of supramolecular nanostructures is still a great challenge. Here, we fabricate a series of supra-amphiphiles by utilizing the recognition motifs based on a heteroditopic porphyrin amphiphile and its zinc complex. These porphyrin amphiphiles can bind with a few guests including Cl
, coronene, C
, 4,4'-bipyridine and 2,4,6-tri(pyridin-4-yl)-1,3,5-triazine, which are further applied to facilitate the controllable self-assembly. Addition of these guests result in the formation of various supra-amphiphiles with well-defined structures, thus induce the generation of different aggregates. A diverse of aggregation morphologies including nanospheres, nanorods, films, spheric micelles, vesicles and macrowires are constructed upon the influence of specific complexation, which highlights the present work with abundant control on the shapes and dimensions of self-assemblies.
•Tofu whey wastewater was an efficient medium for the culture of C. pyrenoidosa.•A concentration of 2.01 g/L was obtained using pure TWW at autotrophic cultures.•High lipid and protein productivities ...were achieved at all trophic modes.
Tofu whey wastewater (TWW) is an abundant, nutrient riched and safety wastewater and is regarded as an excellent alternative medium in fermentation. In this study, the feasibility of algal cultivation using TWW as the basal medium was investigated. Results indicated that through simple pH adjustment, TWW presented a better culture performance at autotrophic, heterotrophic, and mixotrophic modes compared with that of regular green algae medium, BG-11. The biomass productivities of Chlorella pyrenoidosa at each trophic mode were 4.76, 1.97, and 2.08 times higher than that cultured in BG-11 medium, respectively. Although a comparative or even lower lipid and protein content was obtained, much higher lipid and protein productivities were obtained in TWW compared to that of BG-11. The algal biomass accumulated in TWW can be used to produce high-value products. Therefore, TWW is a better alternative medium for efficient algal culture.
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